Xie Xiaowen, Ren Zhenzhen, Su Huihui, Abou-Elwafa Salah Fatouh, Shao Jing, Ku Lixia, Jia Lin, Tian Zhiqiang, Wei Li
College of Agronomy, Henan Agricultural University, Zhengzhou, Henan, 450046, China.
Agronomy Department, Faculty of Agriculture, Assiut University, Assiut, Egypt.
BMC Plant Biol. 2024 Dec 19;24(1):1209. doi: 10.1186/s12870-024-05951-3.
Maize is a major feed and industrial crop and pivotal for ensuring global food security. In light of global warming and climate change, improving maize tolerance to water deficit is crucial. Identification and functional analysis of drought tolerance genes have potential practical importance in understanding the molecular mechanisms of drought stress.
Here, we identified a maize Homeodomain-Leucine Zipper I, ZmHDZ4, in maize seedlings that is associated with drought tolerance. We demonstrated that ZmHDZ4 has transcriptional activation activity, exclusively localized in the nucleus. Several Cis-acting elements associated with abiotic stress have been identified in the core promoter region of ZmHDZ4. Under drought-stressed conditions, transgenic maize plants overexpressing ZmHDZ4 exhibited significantly higher relative water content and peroxidase (POD) and superoxidase dismutase (SOD) activities compared to wide-type plants, while displaying lower malondialdehyde (MAD) content. The expressions of ZmMFS1-88, ZmGPM573, and ZmPHD9 were significantly repressed in the ZmHDZ4-OE plants under drought-stressed conditions, indicating that ZmMFS1-88, ZmGPM573, and ZmPHD9 were the candidate target genes of ZmHDZ4.
ZmHDZ4 is involved in the regulation of drought stress tolerance in maize by participating in osmotic regulation, sugar metabolism pathways, and hormone regulation.
玉米是一种主要的饲料和工业作物，对确保全球粮食安全至关重要。鉴于全球变暖和气候变化，提高玉米对水分亏缺的耐受性至关重要。耐旱基因的鉴定和功能分析对于理解干旱胁迫的分子机制具有潜在的实际意义。
在此，我们在玉米幼苗中鉴定出一个与耐旱性相关的玉米同源异型域-亮氨酸拉链I，即ZmHDZ4。我们证明ZmHDZ4具有转录激活活性，仅定位于细胞核。在ZmHDZ4的核心启动子区域鉴定出了几个与非生物胁迫相关的顺式作用元件。在干旱胁迫条件下，过表达ZmHDZ4的转基因玉米植株与野生型植株相比，表现出显著更高的相对含水量以及过氧化物酶（POD）和超氧化物歧化酶（SOD）活性，同时丙二醛（MAD）含量较低。在干旱胁迫条件下，ZmMFS1-88、ZmGPM573和ZmPHD9在ZmHDZ4-OE植株中的表达受到显著抑制，表明ZmMFS1-88、ZmGPM573和ZmPHD9是ZmHDZ4的候选靶基因。
ZmHDZ4通过参与渗透调节、糖代谢途径和激素调节，参与玉米干旱胁迫耐受性的调控。
